Project Summary/Abstract: The Candidate: This is an application for a K01 award for Dr. Ana-Claire Meyer, a neurologist at the University of California, San Francisco. Dr. Meyer is establishing herself as a young investigator focused on patient-oriented clinical research on infectious diseases of the nervous system in resource-limited settings. Dr. Meyer will obtain additional research training through coursework, tutorials and practical experience in the following areas: applying state-of-the-art research and laboratory methods in tropical medicine, neurophysiology, neuropsychology and neurovirology to global health settings; designing and implementing clinical trials; and additional training in implementation science and global health. With this award, she will obtain the didactic training and mentored clinical research experience she needs to establish herself as an independent researcher and successfully compete for R01 funding. This K01 award will enable Dr. Meyer to take the next steps to achieve her long-term career goal: to become a leading researcher developing, evaluating, and implementing innovative and cost-effective interventions to diagnose and treat neurologic conditions in resource limited settings such as sub-Saharan Africa. The Environment: To support her career objectives and research plan, Dr. Meyer has assembled a multidisciplinary mentoring committee comprised of senior clinical investigators who will provide added expertise in conducting clinical, epidemiological, and translational research on HIV-associated neurocognitive disorders within an international collaborative. Her primary mentor is Dr. Richard W. Price, and her co-mentors are Drs. Gretchen Birbeck and Craig Cohen. Her developing country mentor will be Dr. Elizabeth Bukusi. Her home institution, the University of California San Francisco (UCSF), is considered one of the nation's premier health sciences, training, and research centers and has a well-established reputation in biomedical research. The Department of Neurology is a leading academic center dedicated to excellence in patient care, education and research. The HIV Neurology Research Program conducts clinical and basic science research on the effects of HIV on the nervous system and includes active collaborations with clinical HIV, virology and immunology programs. Her international collaborative site, Family AIDS Care and Education Services (FACES), is an HIV/AIDS care and treatment program based in Kenya. FACES currently provides HIV care in 83 facilities in Nyanza Province and Nairobi. As of December 31, 2010, FACES had 96,821 patients cumulatively enrolled with 37,310 patients on ART. FACES clinical sites have previous experience with research studies. In addition, FACES sites are staffed by well-trained clinicians and ancillary staff and have the necessary infrastructure and oversight to complete this study. Research Plan: We estimate that HIV-associated neurocognitive disorders (HAND) may affect nearly 188,000 individuals in Nyanza Province, Kenya, 5.5 million across sub-Saharan Africa, and 8.25 million worldwide. HAND has been associated with poor adherence to antiretroviral therapy (ART) and with higher mortality. Combination ART is the most effective treatment for HAND to date and some studies have suggested that ART with higher penetration into the central nervous system (CNS) lead to improved neurologic outcomes. However, these studies have important limitations and thus there is insufficient evidence to recommend ART with high CNS penetration effectiveness (CPE) for the treatment of HAND. The objective of this application is to determine whether it is important to treat HIV-infected individuals with neurocognitive disorders with ART with high CPE. Because of limited ART choices in Kenya, we will be able to directly compare the effects of specific ART regimens thus avoiding the limitations of prior studies. The central hypothesis is that, among individuals with HAND, ART with high CPE lead to improved neurologic outcomes as compared to ART with low CPE. We will enroll a prospective observational cohort of 200 HIV-infected ART- na?ve adults with HIV-associated cognitive impairment. Aim 1: To determine the effect of common ART regimens with different CNS pharmacokinetics on the neuro-psychological performance of ART-na?ve HIV infected adults with cognitive impairment in western Kenya Over a follow-up period of 48 weeks, we will determine the effect of four ART regimens on three NP measures: a composite score, the QNPZ-4, and level of impairment using common diagnostic criteria. Aim 2: To determine the effect of common ART regimens with different CNS pharmacokinetics on viral replication and inflammation in the cerebrospinal fluid (CSF) of ART-na?ve HIV infected adults with cognitive impairment in western Kenya In a sub-sample of 100 individuals, we will determine the effect of ART regimens on: (1) CSF HIV-1 RNA; (2) CSF:plasma HIV-1 RNA ratio; (3) CSF WBC count; (4) CSF neopterin. We will also create a unique repository of samples for future collaborative studies. Aim 3: To determine whether there is a practice effect on the neuropsychological test battery We will re-administer our NP battery to 100 HIV un-infected individuals who we have previously studied. These specific aims logically build toward an R01 to determine the effect of ART on combined systemic and neurologic outcomes in cognitively impaired individuals in a randomized controlled trial.